debugger

BaselineWidely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.

Thedebugger statement invokes any available debuggingfunctionality, such as setting a breakpoint. If no debugging functionality is available,this statement has no effect.

Syntax

debugger;

Examples

Using the debugger statement

The following example shows code where adebugger statement has beeninserted, to invoke a debugger (if one exists) when the function is called.

function potentiallyBuggyCode() {  debugger;  // do potentially buggy stuff to examine, step through, etc.}

When the debugger is invoked, execution is paused at thedebuggerstatement. It is like a breakpoint in the script source.

A browser with developer tools open to the debugger panel showing how execution is paused at the debugger statement to allow close inspection of variables, scopes, events, etc.